Pick out your motherboard.
The MSI P43 board looked decent enough to me.
Case...
Depends on your budget.
Low budget?
Get something like a Rosewill Blackbone or Antec Three Hundred.
Mid budget?
Get something like a CM 690 or CM 690 II, Lian Li K7B, K58, or K56.
High budget?
HAF 922, higher priced Lian Li's
Full Tower?
Antec 1200, HAF 932
RAM...
Get 4Gb of some DDR3 1333 or 1600
1600 with CL8 or CL9 timings
1333 with CL7 or CL8 timings
Optical Drive...
Doesn't really matter, just get a DVD burner from like LG, Asus, Samsung, Pioneer, Sony.